GB354409A - Improvements in and relating to electric signalling devices particularly suitable for road traffic purposes - Google Patents

Abstract

354,409. Road-traffic signals. BRITISH THOMSON-HOUSTON CO., Ltd., Crown House, Aldwych, London.-(Assignees of Vickery, H. W. ; 15, Falls Street, Lynn, Massachusetts, U.S.A.) May 13, 1930, No. 14740. Convention date, May 13, 1929. [Class 118 (ii).] In signalling devices for controlling road traffic the electrical signals are operated in sequence by a controller (commutator C) actuated by a motor M, the speed of which may be varied independently for each signal. Means are also provided for overlapping the signals if desired. The commutator C has segments 11 .. 14 connected electrically to rings 15, 16, 17, 16 respectively. Brushes X, Y, Z contact with rings 15, 16, 17 respectively and brush W coacts with segments 11 .. 14. The commutator controls relays T1 .. T4 operating red (R), yellow (Y), and green (G) lamps at the four roads (N, S, E, W) crossing. The motor speed is initially set by rheostat R4. Rheostats R1, R2, R3 are adjusted to control the motor speed for the red, yellow, and green lamps independently of each other, as they are lit up. When brush W touches segment 11 a circuit is closed +ve, 18, W, 11, 15, X, 19, M3, 20, -ve. Magnet M3 is energized and contacts 2 and C2 are bridged to light the red lamps N and S and the green lamps E and W over circuit +ve, 18, 21, C3, 3, 2, C2, lamps, and -ve. Another circuit from 3 also goes through contacts C7 and 7, of relay T3, and through rheostat R1, so that R1 controls the time the lamps just lit remain alight. Similarly, when brush W leaves segment 11 for segment 12, magnets M5 and M6 of relays T3 and T4 are energized to light the yellow lamps on all four roads, N, S, E, W. With brush W on segment 13 magnet M4 of relay T2 lights green lamps N and S and red lamps E and W; whilst with W on segment 14 magnets M5, M6 are again used to light all yellow lamps. If the yellow lights are to come on before the red lamps N and S, say, are extinguished, a switch S1 is closed. W and 11 having lit the red lamps N and S, W and 12 now light all yellow lamps, energizing magnets M5 and M6 ; another circuit +ve, 18, 8, C8, 4, C4, switch S1, M3, 20, -ve is also made. This magnet M3 re-establishes the red lamps N and S so that the red and yellow overlap. A second switch S2 is used to overlap the yellow lights and the green lights N and S.